Featured Research

from universities, journals, and other organizations

New Medicines At Risk From Biodiversity Loss

Date:
October 17, 2003
Source:
Harvard Medical School
Summary:
In a letter published in the October 17th issue of Science, three scientists warn that biodiversity loss could have devastating consequences for drug discovery and the development of new medicines.

In a letter published in the October 17th issue of Science, three scientists warn that biodiversity loss could have devastating consequences for drug discovery and the development of new medicines. "Tropical cone snails may contain the largest and most clinically important pharmacopoeia of any genus in Nature" says lead author of the study, Eric Chivian from the Harvard Medical School, "but wild populations are being decimated by habitat destruction and overexploitation. To lose these species would be a self-destructive act of unparalleled folly."

Related Articles


Approximately 500 species of cone snails inhabit shallow tropical seas. They defend themselves and paralyze their prey – worms, fish, and other molluscs – by injecting a cocktail of toxins through a hollow, harpoon-like tooth. Each species has its own distinct set of around 100 'conotoxins', which like a gourmet chef it mixes in constantly changing proportions, thereby preventing evolution of resistance in their prey. Co-researcher Aaron Bernstein, also of Harvard, says "To date, only about 100 of the estimated 50,000 cone snail toxins have been characterized, and only a handful tested for pharmacologic activity. The results have extraordinary promise for the development of powerful new drugs."

With more than 2600 studies published in the last 20 years, there is much excitement about conotoxins in biomedicine. "Most conotoxins are a succinct ten to forty amino acids in length and are exquisitely selective about their receptor binding sites. This makes them powerful tools for understanding how cells work and a rich source for discovery of new medicines", said Bernstein. Among many discoveries, conotoxins that block key neurological pathways have been effective in the early detection and may also help treat small-cell lung cancer, one of the most devastating human cancers. A compound now in clinical trials has powerful anti-epileptic activity. Experiments suggest that conotoxins could treat muscle spasticity following spinal cord injury. They could prevent cell death when there is inadequate circulation, such as during strokes, head injuries or coronary bypass surgery. They could also be used to treat clinical depression, heart arrhythmias and urinary incontinence.

Conotoxin research has advanced farthest in treatment of pain. The synthetic drug Prialt is in extended Stage III clinical trials for the treatment of intractable pain (unremitting, severe, and essentially untreatable pain) and could soon be on the market. "Prialt may be 1000 times more potent than morphine. More importantly, it does not seem to lead to addiction or tolerance, where increasing doses are required to achieve the same effect" said Chivian. These problems have greatly limited the long-term effectiveness of the current mainstays of severe pain therapy, morphine and other opiates. Many millions of people suffer from intractable pain and have developed tolerance to opiates, so a potent painkiller like Prialt could represent an enormous therapeutic breakthrough.

Just as we are appreciating the remarkable potential of cone snails as a source of new medicines, they are coming under intense pressure in the wild. Their shallow tropical habitats are rapidly being destroyed and snails are being collected at alarming rates from the wild to supply the ornamental shell trade as well as for biomedical research.

Cone snails are exquisitely beautiful and have been coveted by collectors since at least the 16th Century. A rare cone snail shell was sold at an Amsterdam auction in 1796 for more than a Vermeer painting! Collectors still cherish these shells, and rates of capture from the wild are escalating rapidly. "Millions of cone snails are now sold annually for as little as a few cents each in shops all over the world. But we could not find any country that monitors this trade" said co-author Callum Roberts, of the University of York, "Nobody is looking out for them."

Alongside overexploitation, cone snail habitats are being degraded and destroyed by coastal development, overfishing, pollution, disease and global climate change. A quarter of the planet's coral reefs have already been seriously damaged or destroyed and half of the world's mangroves cleared. The risk of global extinction is highest for species with narrow geographic distributions. The study found that one in five cone snail species had global ranges encompassing less than 3500km2 of reef, equivalent to a single medium sized atoll. For example, eight species are unique to the Philippines, the hub of the world's ornamental shell trade. People threaten 97% of Philippine coral reefs and extinctions are inevitable if impacts are not alleviated soon.

Habitat loss and escalating, uncontrolled exploitation make a lethal combination that today threatens with extinction cone snails and many other species of biomedical interest. "International markets can develop rapidly in the modern world, which means that wild populations can be decimated before regulatory agencies see any need to protect them." said Roberts. "For this reason, we believe all internationally traded organisms (whether alive or dead) must be monitored, regardless of whether they are currently listed as threatened. This would allow countries to identify emerging markets and act early enough to prevent depletion." This could be achieved, say the authors, by extending CITES (The Convention on International Trade in Endangered Species) to cover all wild-caught species. Meanwhile, at the earliest opportunity cone snails should be added to Appendix II of CITES, so requiring countries to monitor trade and prevent overexploitation.

"Wild nature has been the template for most of the medicines we use today but we have barely even begun to tap its potential", said Chivian, "If we fail to protect cone snails, the loss to future generations would be incalculable."


Story Source:

The above story is based on materials provided by Harvard Medical School. Note: Materials may be edited for content and length.


Cite This Page:

Harvard Medical School. "New Medicines At Risk From Biodiversity Loss." ScienceDaily. ScienceDaily, 17 October 2003. <www.sciencedaily.com/releases/2003/10/031017073822.htm>.
Harvard Medical School. (2003, October 17). New Medicines At Risk From Biodiversity Loss. ScienceDaily. Retrieved November 23, 2014 from www.sciencedaily.com/releases/2003/10/031017073822.htm
Harvard Medical School. "New Medicines At Risk From Biodiversity Loss." ScienceDaily. www.sciencedaily.com/releases/2003/10/031017073822.htm (accessed November 23, 2014).

Share This


More From ScienceDaily



More Plants & Animals News

Sunday, November 23, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Ebola-Hit Sierra Leone's Late Cocoa Leaves Bitter Taste

Ebola-Hit Sierra Leone's Late Cocoa Leaves Bitter Taste

AFP (Nov. 23, 2014) The arable district of Kenema in Sierra Leone -- at the centre of the Ebola outbreak in May -- has been under quarantine for three months as the cocoa harvest comes in. Duration: 01:32 Video provided by AFP
Powered by NewsLook.com
Anglerfish Rarely Seen In Its Habitat Will Haunt You

Anglerfish Rarely Seen In Its Habitat Will Haunt You

Newsy (Nov. 22, 2014) For the first time Monterey Bay Aquarium recorded a video of the elusive, creepy and rarely seen anglerfish. Video provided by Newsy
Powered by NewsLook.com
Birds Around the World Take Flight

Birds Around the World Take Flight

Reuters - Light News Video Online (Nov. 22, 2014) An imperial eagle equipped with a camera spreads its wings over London. It's just one of the many birds making headlines in this week's "animal roundup". Jillian Kitchener reports. Video provided by Reuters
Powered by NewsLook.com
Could Your Genes Be The Reason You're Single?

Could Your Genes Be The Reason You're Single?

Newsy (Nov. 21, 2014) Researchers in Beijing discovered a gene called 5-HTA1, and carriers are reportedly 20 percent more likely to be single. Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:

Strange & Offbeat Stories


Plants & Animals

Earth & Climate

Fossils & Ruins

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins